Field of the Invention
The invention relates to a virtual reality system, and more particularly to a head mounted display apparatus for a virtual reality system.
Description of the Related Art
Displays with virtual image generation are often used in display devices which are located close to the eyes, so-called near-to-eye displays. Such display devices are known, for example, as head mounted displays (HMD).
An HMD is a display device that a person wears on the head in order to have video information directly displayed in front of the eyes. HMDs are also known as near-to-eye displays. An HMD has either one or two small CRT, LCD or OLED displays with magnifying lenses and other optical elements. The displays and optics are typically embedded in a helmet, glasses, or a visor, which a user can wear. Lenses and other optical components are used to give the user the perception that the images are coming from a greater distance, to prevent eyestrain. In HMDs that use a single display, the image is typically projected through optics that split the image into two identical images, and redirects each image to the respective eye. With two displays, the HMD can show stereoscopic images. The stereoscopic images attempt to create depth in the images by simulating the angular difference between the images viewed by each eye when looking at an object, due to the different positions of the eyes. This angular difference is one of the key parameters the human brain uses in processing images to create depth perception or distance in human vision.